Biometria de frutos e sementes e germinação de jatobá-curuba (Hymenaea intermedia Ducke, Leguminosae - Caesalpinioideae)

Abstract

(Fruit and seed biometry and germination of jatoba-curuba (Hymenaea intermedia Ducke, Leguminosae-Caesalpinioideae), Hymenaea intermedia Ducke is a tree species of great load, found in forest areas in the states of Pará and Amazonas, Brazil. The objective of this work was to study the biometrical characteristics of fruits and seeds of H. intermedia and the effect of scarification on seed germination. It was measured the length, width and thickness of the fruits and seeds and the number of seeds per fruit. For control and scarified seeds it was measured the percentages and mean time germination and abnormal seedlings and percentage of dead seeds. The seeds scarification was accomplished with an electric emery, in the basal part of the seed. The sowing was done on a substrate of sand and sawdust (1:1), in four replications of 50 seeds, in a complete randomized design. Length, width and thickness of fruits ranged from 26.3 to 54.8 mm, 19.1 to 43.8 mm and 17.7 to 29.6 mm, respectively. The fruits had from one to three seeds, the percentage of damaged seeds by insects (4.1%) was low. Length, width and thickness of seeds ranged from 18.7 to 27.4 mm, 12.2 to 16.1 mm and 10.9 to 15.6 mm, respectively. Statistical difference (p ≤ 0.05) between treatments was detected just for mean germination time. Scarified and control seeds had mean germination time of 18.9 and 68.6 days, germination percentages were 96.0% and 95.5%, obtained at the 25th and 418th days, respectively. As H. intermedia seeds have impermeable tegument to water, mechanical scarification is an efficient method of breaking seed dormancy in this species.